the traditional BCEL-based weaver is a mature technology that handles all of Java 7 and OT/J, but it cannot handle Java 8 class files.

a new ASM-based weaver will be first released with Luna, which can handle all elements of Java 8 byte code. Additionally, this weaver is capable of runtime weaving (as opposed to load-time weaving), However, this weaver needs more maturing before being enabled as the default

to support both weavers, the compiler can produce class files in two alternative formats.

OTDT

Provide essential IDE support for the combination of Java 8 features with OT/J